view docs/html/sdlpalette.html @ 2042:3908e1f808e1

Fixed bug #292 I might be on crack here. It looks like SDL_ConvertMono() in src/audio/SDL_audiocvt.c adds the left and right channels of a stereo stream together, and clamps the new mono channel if it would overflow. Shouldn't it be dividing by 2 to average the two sample points instead of clamping? Otherwise the mono sample point's volume doubles in the conversion. This would also make the conversion faster, as it replaces two branches per sample frame with a bitwise shift. --ryan.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 24 Sep 2006 15:56:36 +0000
parents 355632dca928
children
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><H1
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>SDL_Palette</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN3129"
></A
><H2
>Name</H2
>SDL_Palette&nbsp;--&nbsp;Color palette for 8-bit pixel formats</DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3132"
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><H2
>Structure Definition</H2
><PRE
CLASS="PROGRAMLISTING"
>typedef struct{
  int ncolors;
  SDL_Color *colors;
} SDL_Palette;</PRE
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><H2
>Structure Data</H2
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><TT
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><I
>ncolors</I
></TT
></TD
><TD
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>Number of colors used in this palette</TD
></TR
><TR
><TD
ALIGN="LEFT"
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><TT
CLASS="STRUCTFIELD"
><I
>colors</I
></TT
></TD
><TD
ALIGN="LEFT"
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>Pointer to <A
HREF="sdlcolor.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Color</SPAN
></A
> structures that make up the palette.</TD
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><H2
>Description</H2
><P
>Each pixel in an 8-bit surface is an index into the <TT
CLASS="STRUCTFIELD"
><I
>colors</I
></TT
> field of the <SPAN
CLASS="STRUCTNAME"
>SDL_Palette</SPAN
> structure store in <A
HREF="sdlpixelformat.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_PixelFormat</SPAN
></A
>. A <SPAN
CLASS="STRUCTNAME"
>SDL_Palette</SPAN
> should never need to be created manually. It is automatically created when SDL allocates a <SPAN
CLASS="STRUCTNAME"
>SDL_PixelFormat</SPAN
> for a surface. The colors values of a <A
HREF="sdlsurface.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Surface</SPAN
></A
>s palette can be set with the <A
HREF="sdlsetcolors.html"
><TT
CLASS="FUNCTION"
>SDL_SetColors</TT
></A
>.</P
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><H2
>See Also</H2
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><SPAN
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>SDL_Color</SPAN
></A
>,
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><SPAN
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>SDL_Surface</SPAN
></A
>,
<A
HREF="sdlsetcolors.html"
><TT
CLASS="FUNCTION"
>SDL_SetColors</TT
></A
>
<A
HREF="sdlsetpalette.html"
><TT
CLASS="FUNCTION"
>SDL_SetPalette</TT
></A
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